Simulation Analysis of RF Pulse Aiming at SAR Reduction of MRI

概要

論文の詳細を見る
We improve the waveform of the Radiofrequency (RF) pulse for the purpose of reducing the Specific Absorption Rate (SAR) of MRI equipments. Two RF waveforms are examined: the standard ±2π sinc function muldplied by a double exponendal function (sincDE), and the sincDE multiplied by a correctional function (sincDEF). We simulate the RF excitations of magnetization resulting from our RF pulses by solving the Bloch equation numerically, and evaluate the slice characteristics and the phase diagram of the magnetization. The results for our RF pulses are comparable to those for the standard ±2π sinc function. The areas (integrations with respect to time) of sincDE and sincDEF are 65.8% and 87.0% that of the standard ±2π sinc function, respectively. Both rectangle ratios of the frequency characteristics of sincDE and sincDEF are 115.5% that of the standard ±2π sinc function, which can be considered to be comparable to that of the standard ±2π sinc function. It is thought that the reductions of the areas of RF pulses decrease SAR.
Medical Imaging and Information Sciencesの論文